Patents Assigned to National Power Systems, Inc.
  • Patent number: 5814966
    Abstract: A method and apparatus are disclosed for improving the efficiency of operation of AC induction motors. The method and apparatus utilizes a microprocessor to tune a motor control system such that the time interval between the turn-on of a bi-directional switch and the time of sensing the resultant inrush current through the stator is maintained substantially constant as the load is varied.
    Type: Grant
    Filed: February 12, 1996
    Date of Patent: September 29, 1998
    Assignee: National Power Systems, Inc.
    Inventors: David L. Williamson, Ryan Corley
  • Patent number: 5682091
    Abstract: A method and apparatus for improving the efficiency of operation of polyphase AC induction motors. The method and apparatus utilizes a microprocessor to tune a motor control system such that time interval on at least two phases of a multi-phase power source such that the time intervals between turn-on of bi-directional switches and the time of sensing the resultant inrush currents of the two phases on two motor stators are maintained substantially constant as the load is varied.
    Type: Grant
    Filed: March 20, 1996
    Date of Patent: October 28, 1997
    Assignee: National Power Systems, Inc.
    Inventors: David L. Williamson, Ryan Corley